This fixes in a segmentation fault when dropping a `BackingStore`
constructed through `ArrayBuffer::new_backing_store_from_boxed_slice()`
from an empty slice, since zero length boxed slices are invalid
(dangling) pointers, while Rust expects a `Box<c_void>` to always be a
valid pointer.
Fixes: #849
This patch includes a test for this issue.
The V8 patch is intentionally left simple to avoid merge conflicts in
the future. To be landed upstream, the `unwindinfo_use_count_` would
probably have to be made non-atomic and we'd have to add a cctest.
Upstream bug: https://bugs.chromium.org/p/v8/issues/detail?id=12393
Fixes: #714
The pointer returned by `BackingStore::data` might be null if the
backing store has zero length, but the return type `*mut c_void` does
not force the user to consider this case. This change makes the return
type `Option<NonNull<c_void>>`, which is semantically equivalent, but
which forces users of the API to handle the `None` case.
This is a breaking API change.
For zero-size `BackingStore`s, it seems like `BackingStore::data` always
returns a null pointer. The `Deref` impl for `BackingStore` called
`std::slice::from_raw_parts` on that pointer, even though it is UB to
call that function on a null pointer even for empty slices. This change
fixes that by obtaining a valid pointer from `NonNull::dangling()` if
the original is null.
Reported in
https://github.com/denoland/rusty_v8/issues/711#issuecomment-950637136.
Best case, it produces serialized output that cannot be deserialized.
Worst case, it hits this assert in V8:
# Fatal error in v8::FromJust
# Maybe value is Nothing.
Serializing `new String("")` requires that the wire format header is
written, otherwise V8 assumes an incompatible legacy wire format when
deserializing.
The test started a new thread that slept for a bit, then terminated the
isolate, assuming that the delay was long enough for the isolate and the
context to get fully initialized. It wasn't.
Fixes #710.
This commit adds the following methods:
* `FunctionTemplate::inherit()`
* `FunctionTemplate::prototype_template()`
* `FunctionTemplate::read_only_prototype()`
* `FunctionTemplate::remove_prototype()`
